I just need a little clarification. I made a GPX track file and opened it in JOSM and then downloaded the corresponding OSM data. Here is where I'm confused... Am I supposed to "merge" my GPX track into the OSM data -- OR -- am I supposed to use my GPX track as a visual reference and draw nodes (trace) into the OSM data? asked 19 Nov '11, 09:06  Pilot Guy |
3 Answers:
You can do both:
or
The later is far preferrable and with a bit of practice just as fast and gives better results. In particular you can interpolate the "true" position of the way by using multiple tracks instead of just using one which in general will have large errors. SImon answered 19 Nov '11, 09:17  SimonPoole ♦ edited 19 Nov '11, 09:20 |
Have you read the beginners guide and watched the video tutorials https://wiki.openstreetmap.org/wiki/Video_tutorials they could be a great help.Its good to upload the trace as others can use it to get a good average trace as most traces have some small and often larger errors. Using your knowledge gained when making your trace, and using the other traces together with the bing background (if available) will give the best results when you plot the nodes and make the ways. good luck answered 21 Nov '11, 17:57  andy mackey |
Preferably draw them manually. A tool to merge multiple tracks into one average, more precise, would be nice, but I do not know about one. See this related question: https://help.openstreetmap.org/questions/8844/convert-track-to-road answered 03 Dec '11, 13:03  LM_1 |
What Simon mentions is that the GPS traces are never completely accurate. (Many people believe GPS is always very accurate, this is not true). Using multiple traces and estimating an average position creates a much better result. If you upload your GPX traces you can share yours with other people in the same area or ones you made on another day, to improve the overall result. Drawing over the multiple traces is therefore the best way.
I always do the second of those. I don't really trust GPS traces to be accurate. Your memory of the event can also be very important to resolve glitches.
The second choice is better: If you convert your track into a way, you anyway have to connect it manually to already existing roadways. This also takes time. So manually trace it right from the start, the chances to forget connecting nodes, as well as creating duplicate geometry, are less.